1. Field of the Invention
The present invention relates to comestible and beverage containers. More specifically, the present invention relates to products and methods for sealing containers for consumables.
2. Description of the Prior Art
Consumable containers are evolving rapidly to satisfy the many divergent functional and commercial considerations that drive the food and drink industry. Containers assume an inexhaustible number of configurations, constructed from a wide variety of materials, such as pulp wood sheet stock and glue. Typically, the stock material is configured into an appropriate container shape. A bonding and/or sealing agent, "fixant" hereinafter, is applied to the edges of the flaps or gusset tips of the container. Theoretically, the fixant cures, maintaining the shape of the container. However, fixing the container is problematic in many respects.
First, containers often leak. The fixant is not always introduced into the areas requiring fixant. Sometimes bubbles form in the fixant that rupture, disintegrating the adhesion or seal. These fixing problems are largely attributable to the application means. Many container manufacturers employ applicators or glue guns to apply fixant to seal the containers. Conventional applicators can not be manipulated into every area and inject fixant where needed. Also, the fixant sprayed by the applicator exhibits anisotropic curing characteristics throughout the mass of the fixant: portions of the fixant have cured relative to other portions. A portion of the fixant adheres to the walls of the conduit conveying it from the reservoir to the tip of the applicator. Eventually, the Venturi effect created by the fixant flowing through the conduit draws some of this older fixant back into the stream and out through the tip onto the target fixing zone. This partially cured fixant does not seal the container gussets as effectively as fresher fixant which cures in toto at the gussets. A need exists for a fixant applicator and application method therefor that improves application accuracy, reduces bubble formation therein and eliminates introduction of partially cured fixant to the fixing zone.
Second, containers sometimes present potential health and safety risks to consumers. Occasionally foreign matter may mix with and contaminate the consumable. Again, the fixant application means are significantly responsible. To avert leakage problems, container manufacturers introduce excess fixant into the container. A portion of this excess fixant forms into pellets or strings that break off. These fragments may be ingested by a consumer with unfortunate consequences. A need exists for a fixant applicator and application method therefor that reduces the potential for fragment formation within a container.
Third, container manufacturing is inefficient and wasteful. As mentioned above, container manufactures introduce excess fixant into the container to insure it is sealed. Fixant is expensive. Deploying excess fixant is a cost that could be avoided. Also, cycle time for manufacturing the containers is increased when an excess amount of fixant is applied to the container. This cycle time is further increased by the additional cure time that attends the deposition of a large volume of curable material. A need exists for a fixant applicator and application method therefor that reduces the amount of fixant required to seal the container and reduces the amount of time required to apply liquid to and cure fixant on the fixing zone.
The patent literature is replete with many inventions that address some of the issues discussed above. However, none include a caulk or sealant, configured to complement target fixing zones, that may be carried on a wafer, configured such that the fixant applicator may not be voided from a container. For example, U.S. Pat. No. 3,474,951, issued Oct. 28, 1969, to H. B. Egleston et al., and U.S. Pat. No. 3,998,378, issued Dec. 21, 1976, to W. Vetten, describe container closures involving local heat sealing of container panels. Following Egleston et al., once the container is formed, the overlying panels are heat-pressure sealed with a heating element or die having a design generally corresponding to the outline shape of the target fixing zone. The heating element causes the local flow of the thermoplastic coating on the sheet material that defines the container. According to Vetten, heat is applied to a broader area of the container, then the target zones are locally compressed.
U.S. Pat. No. 4,801,073, issued Jan. 31, 1989, to J. Farber, describes a folding box having a rectangular liquid-tight cemented bottom. The panels defining the box have notches that provide access to the inner panels such that they may be "filmed over with the coating material 6, preferably plastic." Column 2, lines 17-18. The patent describes a "pile up of coating material," at column 1, line 64, however, this refers to the layer "filmed over" the extant layers of coating on both sides of the sheet material defining the container.
U.S. Pat. No. 3,913,825, issued Oct. 21, 1975, to M. A. Brownlee et al., describes a leak proof bottom for a paperboard container. During the blanking of the thermoplastic container stock, a narrow band of thermoplastic material is deposited on the interior side of one of the bottom-forming flaps. The blank is formed to define the container; the flaps are brought into contact and heat sealed.
Clearly the above demonstrates a need for a container fixant applicator and method for producing and application therefor that includes a caulk or sealant, configured to complement target fixing zones, that may be carried on a wafer, configured such that the fixant may not be voided from a container.
None of the above are regarded as describing or teaching the present applicators, production, or application method.